Different firing modes or frequencies occur in the brain and/or other neuronal tissue, for example tonic firing and burst firing (irregular or regular burst firing). Such firing modes can be utilized for normal processing of information, however, alteration of the firing modes, may also lead to pathology.
For example, certain neurological conditions are associated with hyperactivity of the brain and can be traced to a rhythmic burst firing or high frequency tonic firing (e.g., tinnitus, pain, and epilepsy). Other conditions can be associated with an arrhythmic burst firing or a desynchronized form of tonic and burst firing (e.g., movement disorders and hallucinations).
During the past decade, neuromodulation systems have been used to modulate various areas of the brain, spinal cord, or peripheral nerves (See, for example, U.S. Pat. Nos. 6,671,555; 6,690,974). These types of systems utilize tonic forms of electrical stimulation. The disadvantage to these systems is that the neurological condition is related to a high frequency tonic rhythm or bursting type rhythm, it may be difficult for a second tonic stimulation to alter the diseased stimulation to actually result in treatment.
Thus, the present invention is the first to describe a neuromodulation design or stimulation parameters in which the stimulation parameters produce burst stimulation to override or alter the pathological and/or physiological stimulation to treat a neurological condition.